James Jacobs (Paizo's Creative Director) has once declared that there are as many ways to create gates as necessary for the adventure being written:
Are there other ways to create portals?
Yes. There are as many ways to create portals as the writer of an adventure or supplement that requires portals to play a role can make up.
With that said, there is really nothing that prevents, or will cause trouble, when making a direct conversion from 3.5's rules for creating portals to Pathfinder. If Paizo does release some rules about creating portals, those will not be the only acceptable method for creating them, but just another method.
And this is, in fact, explored in the setting. There are dozens of portals created by different races, from aboleth to elves, using magic or technology. One thing they try to make sure is that the methods are not common knowledge, the knowledge of making portals is either kept secret or is a lost knowledge from an ancient civilization.
The Second Darkness adventure path explores the elf gates to a certain extent, but most of that information is available on the wiki. It is worth checking the second book though, Children of the Void, as it precedes the book about the other planets and shows us the first information about using gates and planetary travel in the setting.
James Jacobs words are confirmed on the Distant Worlds setting book (page 53):
From a game perspective, portals are the easiest means
of travel for GMs to manage, as it allows them to control
when such travel is possible and where on a given world
a party appears, as well as creating natural adventure
hooks. Whether they’ve been carefully searching for such
a gateway or simply stumble upon it in the center of a
dungeon, it’s hard for PCs to resist stepping through a
portal and seeing what’s on the other side.
Every planet on the book has a short list of adventure hooks, nearly all of them have at least one entry related to the gate on that planet.
Best Answer
Your 'world' will dictate for the most part how magic is viewed.
NPCs - how other characters react to mages,spells, magic items etc. are a good way to add a sense of how magic is regarded in your game world. A glowing item or demonstration of magic frightens or amazes passersby.. when word reaches a towns ruler of adventurers with a unusual item or abilities she requests an audience to see for herself.
Abundance vs Scarcity - The less there is the more novel magic becomes. If every goblin enountered is wandering around with enchanted daggers and there's a magical supplies merchant in every town its very difficult to maintain a sense of wonder. On the other hand if magic items can only be found after herculean efforts (slaying the dragon etc..) or in exotic locations (in a secret chamber beneath the ancient ruins of a legendary castle ).
Mysterious behavior - Sure that longsword gives you a +1 when fighting orcs. It also cries out the name 'Larissa' under a full moon, Or simply dissapears from time to time... Your mages 'Magic Missile' spell, instead of appearing as glowing arrows every now and then manifests itself differently (a flaming spear, or icy daggers) perhaps modifying its game affect slightly (and unexpectedly!)
Description - be vague in the descriptions/naming of spells/items, the Call of Cthulhu spell list is deliberately obtuse in places (and encourages the Keeper to do the same), an Identify spell for a wand of fireball gives the mage a vision of enemies perishing in flames or suchlike.